This invention relates to a disposable diaper and to more particularly a disposable diaper formed with a feces retaining pocket.
Japanese Unexamined Patent Application Publication No. 2002-315778 (hereinafter “Reference”) discloses a diaper, in which a body fluid absorbent first core is sandwiched between a liquid-pervious sheet and a liquid-impervious sheet to form a relatively large panel extending over a front waist region, a rear waist region and a crotch region. Such a large panel is formed with a feces retaining depression. In this diaper, a relatively small panel comprising a body fluid absorbent second core covered with a liquid-pervious sheet is formed so as to overlap the front waist region and a part of the crotch region on the inner side of the diaper. This relatively small panel covers a part of the feces retaining depression of the relatively large panel in the crotch region so that a pocket opening toward the rear waist region is defined between these relatively large and small panels. Feces flowing from the rear waist region toward the crotch region is reliably received.
The feces retaining pocket of the diaper disclosed in Reference has a size when it is fully opened depending on a vertical dimension from f bottom of the depression to the smaller panel and a transverse dimension of the depression. To ensure that the pocket is adequately opened, the side of the pocket may be dimensioned as largely as desired. However, if a depth of the depression is increased in order to meet this requirement, a thickness of the larger panel will be correspondingly increased and the crotch region of the diaper will become correspondingly bulky. From another viewpoint, if the core of the smaller panel is swollen and/or a stiffness of this core is reduced as the smaller panel absorbs body fluid, the smaller panel may hang into the depression so as to reduce the opening size of the pocket and make it difficult for the pocket to receive feces reliably.